= radiusd(8)
Alan DeKok
:doctype: manpage
:release-version: 4.0.0
:man manual: FreeRADIUS
:man source: FreeRADIUS
:manvolnum: 8

== NAME

radiusd - Authentication, Authorization and Accounting server

== SYNOPSIS

*radiusd* [*-C*] [*-d* _config_directory_] [*-f*] [*-h*] [*-l*
_log_file_] [*-m*] [*-n* _name_] [*-s*] [*-t*] [*-T*] [*-v*] [*-x*]
[*-X*]

== DESCRIPTION

FreeRADIUS is a high-performance and highly configurable RADIUS server.
It supports many database back-ends such as flat-text files, SQL, LDAP,
Perl, Python, etc. It also supports many authentication protocols such
as PAP, CHAP, MS-CHAP(v2), HTTP Digest, and EAP (EAP-MD5, EAP-TLS, PEAP,
EAP-TTLS, EAP-SIM, etc.).

It also has full support for Cisco's VLAN Query Protocol (VMPS) and DHCP.

Please read the DEBUGGING section below. It contains instructions for
quickly configuring the server for your local system.

== OPTIONS

The following command-line options are accepted by the server.

*-C*:: 
  Check the configuration and exit immediately. If there is a problem
  reading the configuration, then the server will exit with a non-zero
  status code. If the configuration appears to be acceptable, then the
  server will exit with a zero status code.
+
Note that there are limitations to this check. Due to the complexities
involved in _almost_ starting a RADIUS server, these checks are
necessarily incomplete. The server can return a zero status code when
run with `-C`, but may still exit with an error when run normally.
+ 
See the output of `radiusd -XC` for a list of which modules are
checked for correct configuration, and which modules are skipped,
and therefore not checked.

*-d config_directory*:: 
  Defaults to `/etc/raddb`. `Radiusd` looks here for its configuration
  files such as the `dictionary` and the `users` files.

*-f*::
  Do not fork, stay running as a foreground process.

*-h*::
  Print usage help information.

*-l log_file*::
  Defaults to `$\{logdir}/radius.log`. `Radiusd` writes its logging
  information to this file. If `log_file` is the string `stdout`, then
  logging messages will be written to stdout.

*-m*::
  On SIGINT or SIGQUIT exit cleanly instead of immediately. This is most
  useful for when running the server with "valgrind".

*-n name*::
  Read `raddb/name.conf` instead of `raddb/radiusd.conf`.
+
Note that by default, the server looks for a configuration file
which matches its own name.  Creating a soft link from file `foo`
to `radiusd`, and then running the program `foo`, will cause the
binary to look for `raddb/foo.conf`.

*-s*::
  Run in "single server" mode. The server normally runs with multiple
  threads and/or processes, which can lower its response time to
  requests.  In single server mode, the server will not "daemonize"
  (auto-background) itself.

*-t*::
  Do not spawn threads.

*-T*::
  Always add timestamps to log messages.

*-v*::
  Print server version information and exit.

*-X*::
  Debugging mode.  This argument is equivalent to using `-sfxx -l
  stdout`. When trying to understand how the server works, ALWAYS run
  it with `radiusd -X`. For production servers, use the `raddebug`
  program.

*-x*::
  Finer-grained debug mode. In this mode the server will print details
  of every request to the default logging destination.  Using multiple
  `-x` options will increase the debug output.

== DEBUGGING

The default configuration is set to work in the widest possible
circumstances. It requires minimal changes for your system.

However, your needs may be complex, and may require significant changes
to the server configuration. Making random changes is a guaranteed
method of failure. Instead, we STRONGLY RECOMMEND proceeding via the
following steps:

1) Always run the server in debugging mode ( `radiusd -X` ) after
making a configuration change. We cannot emphasize this enough. If you
are not running the server in debugging mode, you _will not_ be able to
see what is doing, and you _will not_ be able to correct any problems.

If you ask questions on the mailing list, the first response will be to
tell you "run the server in debugging mode". Please, follow these
instructions.

2) Change as little as possible in the default configuration
files. The server contains a decade of experience with protocols,
databases, and different systems. Its default configuration is designed
to work almost everywhere, and to do almost everything you need.

3) When you make a small change, testing it before changing
anything else. If the change works, save a copy of the configuration,
and make another change. If the change doesn't work, debug it, and try
to understand why it doesn't work.

If you begin by making large changes to the server configuration, it
will never work, and you will never be able to debug the problem.

4) If you need to add a connection to a database FOO (e.g. LDAP
or SQL), then:
 +
a) Edit `raddb/modules/foo`
 +
This file contains the default configuration for the module. It contains
comments describing what can be configured, and what those configuration
entries mean.
 +
b) Edit `raddb/sites-available/default`
 +
This file contains the default policy for the server. e.g. "enable CHAP,
MS-CHAP, and EAP authentication". Look in this file for all references
to your module "foo". Read the comments, and remove the leading hash '#'
from the lines referencing the module. This enables the module.
 +
c) Edit `raddb/sites-available/inner-tunnel`
 +
This file contains the default policy for the "tunneled" portion of
certain EAP methods. Perform the same kind of edits as above, for the
"default" file.. If you are not using EAP (802.1X), then this step can
be skipped.
 +
d) Start the server in debugging mode ( `radiusd -X` ), and start
testing.

5) Ask questions on the mailing list
 +
(freeradius-users@lists.freeradius.org). When asking questions, include
the output from debugging mode ( `radiusd -X` ). This information will
allow people to help you. If you do not include it, the first response
to your message will be "post the output of debug mode".

Ask questions earlier, rather than later. If you cannot solve a problem
in a day, ask a question on the mailing list. Most questions have been
seen before, and can be answered quickly.

== BACKGROUND

*RADIUS* is a protocol spoken between an access server, typically a
device connected to several modems or ISDN lines, and a *radius* server.
When a user connects to the access server, (s)he is asked for a
loginname and a password. This information is then sent to the *radius*
server. The server replies with "access denied", or "access OK". In the
latter case login information is sent along, such as the IP address in
the case of a PPP connection.


== CONFIGURATION

`radiusd` uses a number of configuration files. Each file has its own
manpage describing the format of the file. These files are:

*radiusd.conf*::
  The main configuration file, which sets the administrator-controlled
  items.

*dictionary*::
  This file is usually static. It defines all the possible RADIUS
  attributes used in the other configuration files. You don't have to
  modify it. It includes other dictionary files in the same directory.

*unlang*::
  The processing and policy language used in the server.

== SEE ALSO

radiusd.conf(5), dictionary(5), unlang(5), raddebug(8)

== AUTHOR

The FreeRADIUS Server Project (https://freeradius.org)
